Hello Charlie & AMMRL
2-D H/B spectra are very much sample dependent; I have run some samples which produced excellent results, and others which have been a waste of instrument time - the best results come from samples in which there is at least one proton bound to boron. I have modified the standard-issue hsqc and hmqc sequences for B/H so that users here can easily set up these experiments, but you could start from a basic C/H setup and alter the relevant parameters. If you would like to run a trial, use borane-dimethylsulphide (a bit smelly, but it works quite well) with 1J set at 105 Hz and MJ set at 2.5 Hz. The work currently underway at these will be published sometime early next year; I'll send you a list of references once they are in press.
Regards,
Craig Grimmer.
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>>> lcd_at_mail.pse.umass.edu 8/11/04 6:52:27 PM >>>
I have a user with a messy Boron-11 molecule and we think
something like an 1H{11B} HMQC would be very helpful....
but of course the quadrupolarity B11 gets in the way of this
working. I find nothing yet in my literature searches for 11B
2D. The relaxation times are not too bad...50ms or
so T2. I am wondering what is out there for 'moderately'
quadrupolar heteronuclear correlations. I see that
Berger's '200 & More ..' has a HOESY example with 6Li-1H but
I thought I'd query the AMMRL body of experience before
trying that up for 11B.
Pax et Thanx
Charlie Dickinson
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
+ Charlie Dickinson, PhD -
+ NMR Director -
+ High Field Nuclear Magnetic Resonance Laboratory -
+ Department of Polymer Science and Engineering -
+ University of Massachusetts-Amherst -
+ Amherst MA 01003 USA -
+ PHO (413)577-1428 FAX (413)545-0082 -
+ charlie_at_telemann.pse.umass.edu
Science
Is not what they say it is, so serious
The truth being what you imagine
Not what you see
And not something useful
Or something that pays.
Rebecca Elson
-----------------------------------------
Craig Grimmer
UNPCHEMNMR
School of Chemistry
University of KwaZulu-Natal
Private Bag X01
Pietermaritzburg
3209
South Africa
Tel: +27-33-2605326
Fax: +27-33-2605009
Email: grimmerc_at_ukzn.ac.za
URL: http://chemweb.unp.ac.za/
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<<<<gwavasig>>>>
Received on Wed Nov 10 2004 - 09:12:54 MST